Recipe Tips

Preparation

Place beef, fat side up, in large shallow roasting pan or on rimmed baking sheet. Sprinkle beef all over with salt and pepper. Spread mustard all over beef. Mix rosemary and thyme in small bowl; sprinkle over beef and press lightly to adhere. DO AHEAD Can be prepared 1 day ahead. Cover and refrigerate.

Discard drippings from roasting pan. Place pan over 2 burners on stove top over medium heat. Add butter to pan and melt. Add flour; whisk until smooth and just beginning to color, about 5 minutes. Whisk in stock. Boil until sauce thickens slightly, whisking often, about 10 minutes. Season sauce to taste with salt and pepper. Serve beef with vegetables and sauce.